Cryosurgical spraying apparatus

ABSTRACT

An insulated, compact, mobile cryosurgical instrument is provided that has no moving parts in contact with a liquefied gas coolant retained in an insulated container. Upon interrupting normal venting from the container, the liquefied gas coolant will build up a pressure in the container which pressure can be increased by a squeeze pressure device. The pressure will cause the liquefied gas coolant to spray from a nozzle until normal venting is restored.

United States Patent Waller et al.

[ 1 June 17, 1975 [5 CRYOSURGICAL SPRAYING APPARATUS 3.702.114 11/1972Zacaria: .1585311 3.739.956 6/1973 Reynol s r. l 8 3.l [761 Invemors:gzi t g f 'f gggg iifei 3.823.718 7/1974 Tromovitch l28/303.l

l y 233:: 1 1 32 3 Primary Examiner-Lawrence W. Trapp Sandlin lrower 5 tAttorney, Agent, or FirmTed D. Lee; Donald R. Antonio. Tex. 78232 221'Filed: on. 30, 1974 [57] ABSTRACT PP An insulated, compact, mobilecryosurgical instrument is provided that has no moving parts in contact52 us. 01. l28/303.l with a liquefied coolant mined in an insulated [5!]Int Cl 2 I I I I A Q h A61B 17/36 container. Upon interrupting normalventing from the [58] Field 0'1;;.'.';-jh'II1 128/3031 173 R 400-liquefied gas will build up a pressure in the container which pressurecan be increased by a squeeze pressure device. The pressure [56]References Cited will cause the liquefied gas coolant to spray from aUNITED STATES PATENTS nozzle until normal venting is restored.

3.651.8l3 3/1972 Bryne |28/303.l 6 Claims, 2 Drawing Figures 52 44 42 asso as 54 38 40 56 i 5s 24 TI 25 so 26 l 64 I 62 i 66 -34 y r i l i |4- 7'2 I I r 72 I f I I I ll 5 I I I -I6 -;l8 I I z y. z r

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FIG. 2

CRYOSURGICAL SPRAYING APPARATUS BACKGROUND OF THE INVENTION The presentinvention relates to a cryosurgical instrument and. more particularly.to a liquid nitrogen spray apparatus that can be used in treatinglesions. benign or malignant. that respond to cryosurgery.

In the medical practice there have been various types of sprayingapparatus used in cryosurgery for the treatment of skin lesions. Usinglaymans terms the skin lesions may be any type of definite growth in theskin {warts being an example) or an infection in the skin (acne being anexample). In recent years cryosurgery has been used to treat cancerousor malignant tumors in the skin. The cancerous areas may be located onei ther the internal areas of the body or on the exterior skin.

Regardless of the type of cryosurgical instrument that is used. thelesion must be frozen to at least minus twenty degrees Centigrade toinsure the destruction of all the abnormal cells. Though various typesof liquefied gas coolants may be used in cryosurgical instruments. theusual liquefied gas used by the medical profession is liquid nitrogenwhich has a boiling point of minus 196C. Because of the extremely lowboiling temperature ofliquid nitrogen, it must be stored in specialcontainers to prevent evaporation to the atmosphere. Also. if any movingparts come into contact with the liquid nitrogen they may freeze up orstick due to a moisture collection from the atmosphere. Any flexiblehosing that may come in contact with the liquid nitrogen becomes veryrigid and brittle.

A cryosurgical instrument in common use today by the medical professionis shown in U.S. Pat. No. 3.739.956 issued to Reynolds. a copy of whichis submitted with this patent application. In Reynolds various types ofvalving apparatus and moving parts are shown as coming in contact withthe liquid refrigerant. All of these valving apparatus may freeze up ina very short period of time. Liquid coolant would be evaporated toatmosphere in a very short period of time. As can be seen from Reynolds.it is a fairly complex apparatus that would be expensive to manufacture.

Another apparatus commonly used by the medical profession is theapparatus as shown in the Bryne patent, U.S. Pat. No. 3.534.739. a copyof which is submitted with the present patent application. Though Brynehas the advantage of having no moving parts in contact with theliquefied gas coolant. the coolant is continuously boiling inside of thecontainer and will completely evaporate in a very short period oftime.By stopping of the normal venting from the container the pressure isbuilt up to cause a stream of coolant to be ejected from the nozzle. Ina single operation that may require thirty minutes to perform. theapparatus, as shown in Bryne. would have to be filled repeatedly. Manyoperations require the repeated treatment by the liquid gas coolant overshort time intervals to insure a complete destruction of the lesion.Though the Bryne apparatus is inexpensive to manufacture it is extremelywasteful of the liquid coolant as well as being impossible to use forrepeated time interval treatments without refilling with coolant. Alater version of the same apparatus is shown in US. Pat. No. 3.65l.8l3.a copy of which is also enclosed with the patent application.

Various other types of cryosurgical instruments are shown in thefollowing patents:

Though the applicant will not discuss in detail the above referencedpatents. copies are included with the present patent application for theconvenience of the examiner. Previous discussions of the prior art applyto the referenced patents.

Another apparatus that is being sold in the market today is the TT-32Liquid Nitrogen Sprayer by Physi cians Products Inc.. Box 44. Millbrae.Calif. 94030. Copies of the sales literature is included for theconvenience of the examiner. Since the liquid coolant is contained in avacuum bottle. considerable waste of the liquid coolant is avoided. Thepressure built up inside the vacuum bottle would not normally be enoughto cause a continuous ejection of the liquid coolant from the nozzle.The valving mechanism immediately above the squeeze bulb is inconvenientto operate. One hand must be used to squeeze the bulb and the thumb andforefinger of the same hand or the other hand being used to operate thevalve. The hand not being used on the bulb and valve. or a secondperson, must hold the spray nozzle on the skin lesion and hold thevacuum bottle. After squeezing the squeeze bulb with the valve closedliquid nitrogen is ejected from the nozzle; how ever. liquid nitrogenwill continue to eject from the nozzle until pressure inside the vacuumbottle has been dissipated. This may result in an excess of the liquidcoolant reaching the skin lesion or adjacent normal areas with resultantdamage to skin tissue. Because the valve is a screw type valve it is noteasy to rapidly open and close resulting in a loss of the delicatecontrol of the amount of coolant delivered which is so highly desirablein such a unit especially in treating very sensitive areas about theeyes. face. genitalia. etc.

In the present apparatus a continuously open vent is providedimmediately above the squeeze bulb that may be closed by placing thethumb over the opening. Immediately upon removing the thumb from theopening, the pressure inside the vacuum bottle immediately decreases tostop the ejection of the liquid coolant. This venting mechanism providesan extremely delicate and precise control of the amount of coolantdelivered.

In the TT-32 Liquid Nitrogen Sprayer a safety vent valve is providedimmediately above the vacuum bottle stopper. This valve. which allowsfor the venting to the atmosphere of any excessive pressures has thepotential problem of freezing up due to moisture from the atmosphere.Should this valve freeze up. excess pressures could build up within theunit if the valve above the squeeze bulb is closed. Once the vent valvefreezes the apparatus must be taken apart to allow the vent valve tothaw before the TT-32 Sprayer can be used again. The present inventionwith its continuous open. simple, thumb controlled venting completelyeliminates any possibility of excess pressure building up within theunit. Also, the flexible hose from the vent valve to the spray nozzle ofthe TT-32 Sprayer is impractical. Once liquid nitrogen flows through theflexible hose it becomes very rigid and brittle, This hose may breakeven under hospital conditions due to the extremely brittle conditionscaused by the low temperature. Although the TT-32 is inexpensive anddoes not waste the liquid nitrogen as long as the vent valve remainsopen, its use under hospital conditions is very awkward and inconvenient. The present invention eliminates the problem of the freezing ofthe vent valve, the breaking of the flexible hose through which theliquid nitrogen flows and the inconvenient operation of the squeeze bulbvalve. The present apparatus prevents an excess of liquid ni trogen frombeing applied to the skin lesion because of the extremely precise anddelicate control made possible by the thumb controlled venting. Thepresent invention also incorporates a standard Leur lock head for therapid and easy attachment of tips (needles) of any diameter and lengthnecessary to treat lesions of any size and location.

SUMMARY OF THE INVENTION It is an object of the present invention toprovide a cryosurgical instrument for treating skin lesions, benign ormalignant.

It is another object of the present invention to provide an insulated,compact, mobile cryosurgical instrument that is very easy to use andinexpensive to manufacture.

It is a further object of the present invention to provide acryosurgical instrument that minimizes waste of the liquid coolant, suchas nitrogen.

It is yet a further object of the present invention to provide acryosurgical instrument with no moving parts that contact the liquidnitrogen and, simultaneously, be very economical to manufacture and easyto use in a hospital or office.

It is yet another object of the present invention to provide aninsulated, compact, mobile cryosurgical instrument wherein pressure canbe applied to the liquefied gas coolant and released immediately bymovement of one hand while the other hand maintains the nozzle on theskin lesion being treated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of thecryosurgical spraying apparatus.

FIG. 2 is an elevated cross sectional view of the cryosurgical sprayingapparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2in combination, the cryosurgical spraying apparatus is representedgenerally by the reference numeral 10. The cryosurgical sprayingapparatus has an insulated container 12 that is similar to a commonvacuum bottle. The insulated container 12 has an inner wall 14 and outerwall 16 with a space 18 contained therebetween. The space 18 alsoextends between the bottom 20 of inner wall 14 and bottom 22 of outerwall 16. The upper portion of the insulated container 12 consists of acap 24 threadably connected to the upper portion of outer wall 16 with asealing ring 26 providing a good seal therebetween. The upper portion ofthe insulated container 12 contains an opening 28 through which aliquefied gas coolant may be inserted upon removing the cap 24.

The cap has holes 30 and 32 contained therein. Through hole 32 extendstubing 34 to nearly the bottom 20 of inner wall I4. The tubing 34 shouldbe of a suitable noncorrosive metal substance for receiving a liquefiedgas coolant contained inside of the insulated container 12. The upperportion of the tubing 34 which extends through hole 30 has a ninetydegree bend 36 to the left. Immediately below the 90 bend 36 are threadconnections 38 of tubing 34 to which a suitable retaining nut 40 may beattached. The retaining nut 40 securely locates the tubing 34 and theninety degree bend 36 to the cap 24. To provide a good seal with the capa resilient washer could be used; however, because of the extremely lowtemperature of liquid nitrogen and the brittle nature ofa resilientwasher at these temperatures, a clear epoxy type sealant is used in thepreferred embodiment.

The leftmost portion of the ninety degree bend 36 provides a largenozzle 42 to which needle 44 may be attached. The large nozzle 42 has aLeur type locking head formed by inner tubing 46 and outer structure 48for retaining the needle 44. Slots 50 have been provided in the outerstructure 48 to provide ease of installation of the needle 44 bypreventing the trapping of pressurized air behind the needle 44. Theneedle 44 has a small tip to provide the application of the liquefiedgas coolant to a very localized area. Other types of needles or nozzlesmay be used according to the particular needs of the individual case.

Through hole 32 of cap 24 is inserted a ninety degree flange fitting 54.The lowermost portion of the flange fitting 54 is threadably connectedto nut 56. Again a clear epoxy type sealant is being used to prevent theescape of pressurized gas through holes 32, but it should be understoodthat other types of seals may be utilized. A flexible rubber hose 58 isconnected to flange fitting 54 for fluid communication with the insideof insulated container 12. The opposite end of the flexible rubber hose58 is connected to T-valve 60 with one side of the T-valve having anopening 62 to atmosphere. The opening 62 terminates in a thumb pressflange 64 whereby a thumb of the operator of the cryosurgical sprayingapparatus 10 may cover the opening 62 when the apparatus is being used.The other side of the T- valve 60 is connected to a squeeze bulb 66which may be utilized to pressurize the inside of insulated container 12via flange fitting 54, tubing 58 and T-valve 60. The bottom of squeezebulb 66 has a one-way Reed valve 68 that allows air to flow into thesqueeze bulb 66 but not vice-versa. The Reed valve 68 consists of anopening 70 inside of the squeeze tube 68 which is covered with a thinmetal strip 72. Upon squeezing the squeeze bulb 66 the thin metal strip72 covers the opening 70 to prevent the escape of air through opening70.

In the present invention needle 44 is shown with a small tip 52;however. other types of needles or nozzles may be used including anozzle that would spray a large area for treatment of skin conditionssuch as acne. Particular types of spraying attachments may be desirablewhen treating a cancerous growth, or other skin lesions. Many othertypes of needles may be utilized depending upon the particularsituation.

METHOD OF OPERATION The cap 24 is unscrewed from the insulated container12. The liquid nitrogen is then poured through the opening 28 into theinsulated container 12 and the cap 24 is placed back on the insulatedcontainer 12. The

cap 24 should be tightened until the seal ring 26 provides a good sealwith the outer wall 16. The liquefied gas coolant inside of insulatedcontainer 12 (usually liquid nitrogen) would need a vent to atmosphereto keep excessive pressures from building up because of the extremelylow temperature. In the cryosurgical spraying apparatus a vent isprovided through flange fitting 54, flexible rubber hose 58, T-valve 60and out opening 62. Normally one filling of insulated container 12 willlast an entire working day of 8 hours without refilling.

Whenever the cryosurgical spraying apparatus 10 is needed a person suchas a medical doctor could immediately pick up the apparatus, put thesmall tip 52 of needle 44 to the area being treated and squeeze thesqueeze bulb 66 while simultaneously placing his thumb over opening 62.The squeezing of the squeeze bulb 66 will create a pressure inside ofinsulated container 12 thereby forcing the liquid nitrogen up tubing 32through 90 bend 36 and out through the needle 44. As soon as the desiredamount of liquid nitrogen has been applied to the skin lesion, the thumbcan be removed from thumb press flange 64 thereby uncovering opening 62.This will immediately relieve the pressure inside of insulated container12 thereby stopping the flow of the liquid nitrogen out needle 44. Thisprocess can be repeated as many times as cryosurgical treatment isnecessary during an operation. Because the container is well insulatedthe liquid nitrogen will last for an extended period of time forrepeated treatments.

In the present apparatus there are no moving parts that will come incontact with the liquid nitrogen and therefore be subject to freezingdue to moisture condensation. Also pressure inside of the container canbe relieved immediately by simply removing the thumb from the thumbpress flange 64, thereby stopping the flow of liquid nitrogen thusenabling the treating physician to apply a very controlled amount to alocalized area.

We claim: I. A cryosurgical instrument for treating skin lesionscomprising:

an insulated container for holding a liquefied gas coolant;

cap means for said insulated container;

a combination vent/pressure line communicating with the inside of saidinsulated container;

tubing means extending from near the bottom of said insulated containerto the outside thereof;

nozzle means attached to said tubing means for spraying said liquefiedgas coolant upon pressurization from said vent/pressure line;

said vent/pressure line being connected to atmosphere through a firstopening and to a source of pressurized air through a second opening,said first opening being covered before pressurization through saidsecond opening.

2. The cryosurgical instrument as recited in claim 1 further comprises amanual squeeze bulb for said pressurization through said second opening.

3. The cryosurgical instrument as recited in claim 2 wherein said firstopening is adapted for covering by the thumb of the operator of saidsqueeze bulb to stop venting before pressurization, and toinstantaneously remove pressurization upon uncovering said firstopening.

4. The cryosurgical instrument as recited in claim 3 wherein saidvent/pressure line and said tubing means extends through said cap meansin an airtight manner.

5. The cryosurgical instrument as recited in claim 4 wherein saidinsulated container is a vacuum bottle and said cap means is a cap forsaid vacuum bottle.

6. The cryosurgical instrument as recited in claim 1 wherein said nozzlemeans is interchangeable.

* I t l l

1. A cryosurgical instrument for treating skin lesions comprising: aninsulated container for holding a liquefied gas coolant; cap means forsaid insulated container; a combination vent/pressure line communicatingwith the inside of said insulated container; tubing means extending fromnear the bottom of said insulated container to the outside thereof;nozzle means attached to said tubing means for spraying said liquefiedgas coolant upon pressurization from said vent/pressure line; saidvent/pressure line being connected to atmosphere through a first openingand to a source of pressurized air through a second opening, said firstopening being covered before pressurization through said second opening.2. The cryosurgical instrument as recited in claim 1 further comprises amanual squeeze bulb for said pressurization through said second opening.3. The cryosurgical instrument as recited in claim 2 wherein said firstopening is adapted for covering by the thumb of the operator of saidsqueeze bulb to stop venting before pressurization, and toinstantaneously remove pressurization upon uncovering said firstopening.
 4. The cryosurgical instrument as recited in claim 3 whereinsaid vent/pressure line and said tubing means extends through said capmeans in an airtight manner.
 5. The cryosurgical instrument as recitedin claim 4 wherein said insulated container is a vacuum bottle and saidcap means is a cap for said vacuum bottle.
 6. The cryosurgicalinstrument as recited in claim 1 wherein said nozzle means isinterchangeable.